Press for operating on metal or other sheets



H. A. GRIFFITHS PRESS FOR OPERATING ON METAL OR OTHER SHEETS oct. 14, 1930.

2 Sheets-She'et 1 Filed Aug. 8, 1928 -lOct 14, 1930. v H. A. GRIFFITHS 1,778,493

. PRESS FOR OPERATING ON METAL OR OTHER SHEETS Filed Aug. s, 1928 2 sheets-sheet 2 hf m I T7 Patented Oct. 14, 1930 HARRY ALBERT GRIFFITHS, 0F BIRMINGHAM, ENGLAND PRESS FOR OPERATING ON METAL OR OTHER SHEETS Application led August 8, 1928, Serial No. 298,333, and in Great Britain August 27, 1927.

This invention has for its object to provide an improved press for use in the cut-- ting out of circula-r blanks or other articles from metal or other sheets. l

The invention comprises primarily the employment of a punch or similar tool which is situated below the level of the sheet and is arranged to operate in an upward, instead of the usual downward direct-ion, in combination with means'whereby the blanks or the like cut from the sheet are caused to move relativelv to the machine in al direction opposite to that of the movement of the sheet.

Also the' invention comprises the employment of means whereby the sheet is supported in an inclined position, the sheet being secured at its lower edge and moved in an upward transverse direction at the completionv of each longitudinal movement through the sheet.

Further the invention comprises the combination and arrangement of parts hereinafter described. Y

In the two accompanying sheets of eX- planatory drawings f.

' Figure l is a-side elevation showing diagrammatically one manner of applying my invention to a press for operating on metal sheets. f

Figure 2 is a diagrammatic sectional plan and Figure 3 a diagrammatic sectional end viewof the sheet supporting and ytransverse feeding` mechanism.

In the construction of a machine as shown for cutting out circularblanks from a metal sheet,y and Hanging the same to form the body part or lid of a tin box, a punch or pair of punches a is or are arranged beneath the level of the metal' sheet which is indicated by b, and are reeiprocated in an upward and downward direction from a crank shaft c located beneath the punch or punches near the lower side of the machine. The dies Z withwhichlthepunches co-operate are arranged above the punches. Between the punch and die is mounteda stripper' plate e over which the sheet to be operated on cau traverse. Alongside the cutting tools is arranged a support tor the sheet, the latter being held preferably in a downwardly inclined position. This support comprises a pair of slides f, g, movable on guides L, z', whereby motion in two directions at right angles to each other can be imparted to the sheet. rIhe slide f is adapted in any con venient manner for the attachment to it of the sheet b. The slide g carries the guide 7L.

rlhe longitudinal step by step movement oi' the sheet between the cutting tools along the guidez' may be eiiectcd by means such as those described in the specifications of prior British Patents llos. 237;@ and 277,505. The sheet is gripped at its lower edge by an)rv suitable means. l?re'lerably7 the means described in the prior British Patent No. 257.773 are employed for this purpose. with the addition ot a small movable platform (not shown) which comes into operation to support the edge of the sheet while the latter bein gripped and subsequently remains out ot acti n.

At the end oil each complete longitudinal movement oi: the sheet. an upward, or transverse, movement is imparted to it for the purpose of bringing another portion oi the sheet under the action oi' the tools. To effect this movement automatically, l arrange at opposite sides of the sheet support a pair of bars y' on which a munber oli shoulders are formed or provided at suitable distances apart. Preferably 'the collars on one ha r are staggered in relation to those on the opposite bar, and the distance between any pair ci eollars on either bar is equal to one hzllif et the movement required to be given to the sheet. Each or" the bars jvis mounted to slide at one end in a bearing Z. and at the other d over a. fixed bar m, the latter end of the be. j bei made hollow'to receive the bar m. e

Suitabl reciprocatory movement is imparted to the e parted to gages the rack above mentioned can be renal movement of the sheet valongv the bar In the arrangementA shown the shaft 0 is rocked from a cam p, through a lever g, rod r, lever s, linli t and r'lever et. 'As the cam shown moves the mechanism in one direction only, a spring c is provided to effect the return movement.

In combinatien with the transverseV guide L is also arranged a rack to with which the pawl can engage for preventing accidental return movement of the inclined sheet,`and in combination with the slide which' moves on this guide arranged a pair of pawls g/ for engaging the shoulders on the bars j above mentioned. VVlien thesheet occupies one extreme position as shown, one of the said rp'awls engages a shoulder on one of the bars, so that when the lattkr is actuated the required movementis imparted Vto the sheet for bringing` it from Vone positionk to the next. T'vll/'loch the sheet occupies the other ext-reine position, after'the cutting out of another row ,of blanks, the other pawl comes -nto engage- '.ment with a shoulder on the other bar anc another upward transverse movementv is im` the sheet. The pawl .r which en- Vleased when required forv the purpose of yallowing the sheet andfslide f to be returned to its iliitialvposition.` e

It will be understood that the aXis of each punch and die is at right angles to the plane of vthe sheet and is consequently inclined. Aftera blanlr has been cut out from the sheet it remains in Contact with the punchfuntil ejected, and afterejection it falls from the machine by gravity in a direction opposite to that of the movement of the sheet as indicated by the blanks which are shown by .dotted lines at e, Figure l.

The machine may beV litted with either a singlepunch and die, or with two or more punches and dies. When more than. one puncn and die are used as shown, the amount of longitudinal mot/'ement required to cut out a complete row of blanks is correspondingly reduced. ,y

By this invention a variety' of important practical advantages are obtained. F or eX- ample, byparranging thepunch beneath the l level ofthe sheet, Iam able to avo'id,'without the provision of any special devices, the trap-Y ping of portions of the scrap in the tools. rlhis advantageis supplemented by the fact that the punchings and the sheet movein op-y posite directions, and by lthis fact I also am able to avoid entanglement ofthe punchings with the scrap. Further, by arranging the sheet to move in an upward direction under the action of a gripper acting on its lower edge, I am able to relieve the'attendant of mechanismand the arrangement of the tools,

and consequently for the ,sake of simplicity and clearness only sufficient of the machine has been illustrated to elucidate the invention. i1I have-already mentioned how the longitudinal feeding motions may be .produced and how'tlie sheets may be attachedv to the slidef. e. i Y Having thus described'my invention what I clai-m as new and desire tosecure by Letters `Patentis-k f Y l. In presses for operating onmetal and other sheets, the `combination*comprising a movable tool whicliis situated below-thelevel of .the sheet and is. arranged .to operate in `anupvvard direction, means yfor moving the sheet upwardlyat an inclination and the movable tool being arranged to. operate at an angle to the vertical and perpendicularly to the sheet whereby the parts cut' from theisheet are causedto move relatively to the press in a direction opposite to ,the movementgof. the sheet, substantially as described. i Y

2. In presses as claimed in claim 1,an1inclined support for the sheet, means whereby the sheet is held at' its lower edge, and means wherebyintermittent feeding movements are imparted to the sheet in'an upward direction on the support, substantially yas described.

3. In presses as claimed in claim :1, the combination comprising a pair of slides and guides, oneof which is at right angles to the other, a sheet carrier in combination with one of the slides, a pair o f movable bars, means for releasably and opera-bly connecting the bars and sheet carrier together, and means for imparting sheet feedingmove.- ments to the said movable bars, substantially as described. Y y

4. In presses as claimed in claim i 1, kthe combinationV comprising a pair of'slides and guides, one of'which is at' right angles to the other, a sheet Ncarrier in combination with one of'the'slides, a pair, of'movable bars, means for detachablyl connecting the barsand sheet carrier together, means for imparting sheet punch having its axis inclined and arranged perpendicularly to the sheet on the support and acting against the under surface of the sheet so that parts cut from the sheet will pass downwardly, and means Afor intermittently feeding the sheet upwardly on the support, substantially as and for the purposes set forth.

In testimony whereof I naine to this specification.

HARRY ALBERT GRIFFITHS.

have signed my 

